Sedimentation of carbonates Human alterations:fossil fuel burning:tropical deforestation as new fluxes The"missing sink"soures<sinks Elevated CO:experments Can plants sequester more carbon?Does inereased CO act as fertilizer? Geological time scale changes in cycle Variation in flux and pools among biomes Nitrogen cycle Many oxidized reduced forms Importance of microbes Nitrogen fixation Nitrification Denitrificatio Human alterations:nitrogen saturation Phosphorus cycle Little change in chemistry:form(PO) Lost to inactive sediments in oceans/lakes Importance of mycorrhizae in phosphorus uptake Human alterations:fertilizers,run-off to aquatic systems Sulfur eyele Many oxidizedreduced forms Importance of microbes Human alterations:burning S-coal:acid rain/drainage Discussion organization(ten minutes) Why so much pollution in the present world Relation between Nutrient cycling and pollution? Describe the importance of nutrient cycling? V.Assignment: Matter cyeles/is reused:energy flows:not reused